Agricultural machines such as tractors, combine harvesters and field choppers comprise a relatively large number of actuators for setting operating parameters, which actuators have to be placed in a suitable position in order to achieve a satisfactory harvesting result with appropriate application of resources. These operating parameters include in harvesting machines, for example, the rotational speed of the internal combustion engine, the propulsion speed (which defines the harvested crop throughput rate) as well as operating parameters of harvested crop-processing devices such as, in the case of a field chopper, the cutting height of the harvesting attachment, the feed speed in the intake duct, the number of chopper blades of a chopper drum and the distance between two rollers of a harvested crop post-processing device. In the case of a combine harvester, the threshing parameters and cleaning parameters have to be set. In tractors it is also necessary to make various settings and predefinitions, such as the predefinition of a propulsion speed and penetration depth of a soil working tool when working in soil.
Since, in particular, inexperienced operators such as often used as seasonal workers for harvesting generally experience great difficulty in setting the operating parameters to suitable values, especially since they mainly have to carry out other tasks during harvesting, such as steering, monitoring a transfer process, etc., in the past various systems have been proposed which propose suitable operating parameters to the operator so that the operator can set them or which automatically set the operating parameter. In this respect, reference is made, for example, to the prior art according to EP 0 928 554 A1 which describes a combine harvester with a driver assistance system which, after information about external harvesting conditions has been input, permits a selection of different target predefinitions on the basis of which ultimately proposals for operating parameters are provided. The target predefinitions are, in particular, the area output (throughput rate) and the losses which occur, wherein a weighting of both target predefinitions can also be performed on the basis of a two-dimensional curve in which the losses are plotted as a function of the throughput rate.
EP 2 042 019 A2 describes a driver assistance system which permits the operator to propose a change in an operating parameter of a combine harvesters and then displays an expected tendency for the working result.
EP 0 586 999 A2 presents another driver assistance system in which the operator can input operating parameters of a combine harvester and the weighting of target predefinitions, and the system then outputs expected working results.
In another system “Harvester assistant MDA 120” from Aclantec GmbH from 1995, the operator can select, for the purpose of calculating harvesting processes in advance, whether he predefines a loss or urgency of the harvesting. The system then outputs the respective throughput capacity or the speed for the harvesting process.
EP 2 132 974 A1 describes a field chopper in which the operator can input a target predefinition with respect to the compressibility of the harvested crop which is to be achieved. The operator assistance system checks, on the basis of the cutting length and the moisture of the harvested crop, whether the target predefinition can be achieved, and said operator assistance system displays other suitable operating parameters of the field chopper if the target predefinition does not appear to be achievable.
In the prior art according to EP 0 928 554 A1 there is therefore the possibility of selecting a result parameter (throughput rate and/or losses) which is to be optimized of the working result for an operation which is to be carried out. The operator assistance system then outputs the operating parameter (threshing unit and cleaning setting) to be set, but does not display to the operator which result parameter is actually being achieved. The inexperienced operator is presented here with the difficulty of selecting the result parameter which is to be optimized.
The operator assistance systems according to EP 2 042 019 A2 and EP 0 586 999 A2 leave it to the operator to input different settings of the operating parameter and display an expected tendency or an expected result. The optimization of the operating parameter is therefore not carried out automatically in these operator assistance systems by the operator assistance system but rather by the operator who has to try out a plurality of settings in order to find the optimum setting, which will not always lead to optimum settings.
The operator assistance system according to MDA 120 merely permits the value of the result parameter to be achieved (loss or working speed) to be input and outputs the operating parameters to be set for the combine harvester. Here, the operator must therefore input the value of the optimum result parameter himself, which exceeds the abilities of inexperienced operators.
Finally, EP 2 132 974 A1 knows only a single result parameter, that is specifically the compressibility of the harvested crop. However, many harvesting tasks in which it would be advantageous to optimize other result parameters are conceivable.
The present invention has the object of developing an operator assistance system for a field chopper which is further developed compared to the prior art and in which the abovementioned disadvantages do not occur, or occur to a reduced degree.